Field of the Invention
The disclosure relates to the field of using nonlinear optical photodynamic therapy (NLO-PDT) to cause collagen crosslinking using infrared light and riboflavin in the cornea.
Description of the Related Art
Numerous reports in the scientific literature relate to corneal collagen crosslinking, but none relate to the use of femtosecond lasers to activate photosensitizers in the cornea. Several recent papers report evaluation of collagen crosslinking following femtosecond laser generated tunnels in the cornea, but the researchers did not use the laser to activate a photosensitizer. In the past, crosslinking in the cornea has used UV light to activate the photosensitizer, riboflavin. The disadvantage of this approach is that it uses nonfocused light, which broadly and nonspecifically generates free radicals throughout the tissue volume, wherever the light penetrates.